HPLC测定奥美沙坦酯中的基因毒性杂质

目的 建立HPLC测定奥美沙坦酯中潜在的基因毒性杂质[杂质1 ：N-（三苯基甲基）-5-（4''-溴甲基联苯-2-基）四氮唑,杂质2 ：N-三苯甲基-5-（4'',4''-二溴甲基联苯-2-基）四氮唑]的含量和限度。方法 采用Phenomenex C₁₈柱（250 mm×4.6 mm,5 μm）;流动相：0.1%冰乙酸水溶液-0.1%冰乙酸乙腈溶液（15：85）;检测波长：254 nm;流速：1.5 mL·min^-1;柱温：25℃。结果 杂质1 和杂质2 均在0.030 97~0.247 7 μg·mL^-1内线性良好（r分别为0.999 6和0.998 7）,平均回收率分别为94.37%和94.43%,RSD分别为2.38%和2.72%（n=9）。结论 该方法专属性强,准确、灵敏,可以作为奥美沙坦酯中基因毒性杂质1 和杂质2 的液相分析方法。     

阿哌沙班在大鼠体内药动学/药效学研究

目的 考察阿哌沙班大鼠体内药动学并评价其与药效学的相关性。方法 采用超高效液相色谱-串联质谱（UPLC-MS/MS）测定不同时间阿哌沙班血药浓度并绘制血药浓度-时间曲线,同时测定各时间点凝血酶原时间（PT）延长倍数并绘制药效-时间曲线,对药动及药效进行相关性分析。结果 阿哌沙班以2 mg/kg剂量iv给予大鼠,血药浓度时间曲线下面积（AUC_0-∞）、半衰期（t_1/2z）分别为（4 016.07±1 160.46）μg·h/L、（2.95±1.59）h;以10 mg/kg剂量ig给药,AUC_0-∞、t_1/2z、峰浓度（C_max）、达峰时间（t_max）、生物利用度（F）分别为（17 973.48±3 145.30）μg·h/L、（1.52±0.36）h、（4 949.12±615.38）μg/L、（1.00±0.71）h、89.5%。阿哌沙班以10 mg/kg剂量ig给药后0.5~2.0 h可显著延长PT,以各时间点PT延长倍数对血药浓度作图呈良好的线性关系。结论 阿哌沙班大鼠ig给药F高,吸收迅速,延长PT的效应与血药浓度呈现良好的相关性。     

在体单向灌流法研究阿哌沙班肾衰大鼠肠吸收特性

目的 研究阿哌沙班在肾衰大鼠体内的肠吸收特性,并考察P糖蛋白(P-glycoprotein,P-gp)抑制剂对阿哌沙班吸收行为的影响。方法 选择肾衰大鼠在体单向灌流法进行肠吸收实验,建立大鼠阿哌沙班肠灌流液HPLC分析方法,以考察大鼠在体肠吸收影响因素。结果 阿哌沙班在各肠段的吸收速率常数（K_a）存在显著性差异（P<0.05）,但表观吸收系数（P_app）未见明显差异（P>0.05）;大鼠回肠段的K_a和P_app值随药物浓度的增加而降低;加入 P-gp抑制剂盐酸维拉帕米（0.1 mmol/L）后,阿哌沙班在空肠和回肠段的K_a和P_app值均明显增加。结论 阿哌沙班在各肠段均有吸收;P-gp抑制剂对阿哌沙班在空肠和回肠段的吸收均有明显的促进作用,表明阿哌沙班为P-gp底物,推测其吸收机制为主动转运。     

UHPLC-HRMS定量检测莫西沙星中5种亚硝胺类化合物

目的 基于超高效液相色谱和高分辨质谱建立同时检测莫西沙星中5种亚硝胺类基因毒性杂质的定量分析方法。方法 采用ACE Excel 1.7 C₁₈-PFP(100 mm×2.1 mm，1.7 μm)色谱柱，0.1%甲酸水-甲醇为流动相，0.3 mL·min^-1的流速进行梯度洗脱。采用四极杆高分辨静电场轨道阱质谱在电喷雾正离子条件下运用平行反应监测模式对5种亚硝胺类化合物进行定量检测。结果 5种亚硝胺类基因毒性杂质的定量限均≤0.5 ng·mL^-1。NPYP、NEMA和NDEA的标准曲线在1.0~100 ng·mL^-1(NPIP和NDBA为0.1~100 ng·mL^-1)呈良好线性关系(R²≥0.998)。该方法在盐酸莫西沙星药物中的回收率为93.1%~114.1%，RSD为0.7%~4.6%。结论 本方法结果准确、灵敏度高、重复性好，适用于盐酸莫西沙星中亚硝胺类基因毒性杂质的含量检测。     

HPLC测定奥格列汀中基因毒性杂质残留量

目的 建立奥格列汀原料药中基因毒性杂质的HPLC测定方法。方法 采用Zorbax SB-C₁₈色谱柱（250 mm×4.6 mm,5μm）,进样量：20 μl;流动相为0.1%乙酸水-乙腈（65：35）;流速为1mL·min^-1;紫外检测器,检测波长为220 nm;柱温为25℃,色谱乙腈为溶剂。结果 该方法专属性良好,测得苯磺酸异丙酯在4~60 μg·mL^-1内线性关系良好,平均回收率为98.56%（n=9,RSD=3.78%）,溶液在8 h内稳定。结论 该法操作简便,重复性好,结果准确可靠,可用于奥格列汀原料药中基因毒性杂质的测定。     

HS-GC-MS同时测定沙芬酰胺中磺酸酯类基因毒性杂质

目的 建立同时测定沙芬酰胺原料药中5种磺酸酯类基因毒性杂质（甲磺酸甲酯、甲磺酸乙酯、甲磺酸异丙酯、甲磺酸丙酯、甲磺酸丁酯）的方法。方法 采用顶空进样气相色谱-质谱联用法,在线衍生,RESTEK Rxi-624Sil毛细管柱（30 m×0.25 mm,1.4 μm）,四级杆质量检测器,离子化模式为电子轰击离子化（EI）模式,采集模式为选择离子监测。结果 5种杂质检测限为0.3~1.3 ng·mL^-1,定量限为0.9~4.3 ng·mL^-1;精密度、稳定性、重复性试验的RSD均<5%;浓度在5~300 ng·mL^-1内,5种杂质的峰面积与其相对应的浓度有良好的线性关系,相关系数（r²）均>0.995;回收率为99.4%~100.6%,RSD为0.8%~2.6%（n=9）。结论 该法操作简便,重复性好,结果准确可靠,可用于沙芬酰胺中磺酸酯类基因毒性杂质的测定。     

HPLC测定异维A酸有关物质

目的 建立HPLC测定异维A酸有关物质的方法。方法 色谱柱为NUCLEOSIL 100-3 C₁₈（4.6 mm×150 mm,3 μm）,以甲醇-水-冰醋酸（770：225：5）为流动相,流速为1.0 mL·min^-1;柱温为25℃,检测波长为355 nm。结果 异维A酸峰与杂质H、I、维A酸、强制降解杂质峰分离良好;异维A酸、杂质H、I和维A酸的线性范围分别为0.000 545 5~21.82 μg·mL^-1（r=0.999 9）,0.002 856~7.14 μg·mL^-1（r=0.999 0）,0.002 789~6.97 μg·mL^-1（r=0.999 1）、0.017 07~22.76 μg·mL^-1（r=0.999 6）;检测限分别为0.27,0.60,0.65,5.50 ng·mL^-1,定量限分别为0.55,2.85,2.80,17.00 ng·mL^-1;杂质H、I和维A酸的平均回收率分别为101.57%,102.02%,101.03%,RSD分别为0.5%,0.8%,1.5%。结论 建立的HPLC方法准确、专属性强,可用于异维A酸有关物质的测定。     

HPLC同时测定双氯芬酸钠滴眼液中3种抑菌剂的含量

目的 建立HPLC同时测定双氯芬酸钠滴眼液中羟苯乙酯、硫柳汞和苯扎氯铵含量的方法。方法 用十八烷基键合硅胶为填充剂,以1%三乙胺溶液（磷酸调节pH值至3.0）为流动相A,以甲醇为流动相B,进行梯度洗脱;流速1.0 mL·min^-1,柱温40℃,检测波长254 nm。结果 羟苯乙酯在20.58~205.8 μg·mL^-1、硫柳汞在8.242~82.42 μg·mL^-1、苯扎氯铵n-C₁₂H₂₅取代物在12.88~128.8 μg·mL^-1、苯扎氯铵n-C₁₄H₂₉取代物在6.624~66.24 μg·mL^-1内线性良好（r≥0.999 8）,平均回收率为99.3%~102.5%（n=9）。结论 该方法简单、准确、重复性好,可用于控制双氯芬酸钠滴眼液中羟苯乙酯、硫柳汞和苯扎氯铵的含量。     

HPLC法测定阿奇霉素颗粒中的基因毒性杂质对甲苯磺酸乙酯

目的 建立阿奇霉素颗粒中基因毒性杂质对甲苯磺酸乙酯的高效液相色谱（HPLC）测定方法。方法 采用Waters XBridge C₁₈（250 mm×4.6 mm,5 μm）色谱柱,以磷酸盐缓冲液（2.2 g·L^-1无水磷酸氢二钾溶液,用稀磷酸调节pH值至8.9）为流动相A;甲醇-乙腈（25∶75）为流动相B,进行梯度洗脱,体积流量为1.0 mL·min^-1,检测波长为225 nm,柱温为60℃,进样量为50 μL。进行专属性、线性关系、定量限和检测限、精密度、重复性、回收率、稳定性、耐用性试验。结果 空白溶剂、空白辅料、混合溶液中邻近对甲苯磺酸乙酯的杂质L均不干扰对甲苯磺酸乙酯检测;对甲苯磺酸乙酯质量浓度在0.05～0.20 μg·mL^-1（R²＝0.999 9）与峰面积呈良好线性关系;检测限为0.016 7 μg·mL^-1,定量限为0.050 0 μg·mL^-1;平均回收率为95.76%～96.48%,RSD为0.42%～1.53%;精密度、重复性、稳定性、耐用性均符合要求。3批样品中均未检出对甲苯磺酸乙酯。结论 建立的方法专属性强、灵敏度高、特异性强、准确度高,可用于阿奇霉素颗粒中基因毒性杂质对甲苯磺酸乙酯的限度控制与检测。     

阿哌沙班的合成工艺改进

目的 改进阿哌沙班的合成工艺。方法 以3-吗啡啉-1-（4-硝基苯基）-5，6-二氢吡啶-2（1H）-酮（2）为起始原料，经缩合，氨化和"一锅法"还原和环合反应，得到阿哌沙班（1）。结果 中间体和目标化合物的结构经¹H-NMR、¹³C-NMR、高分辨质谱确证，3步合成总收率为50.2%。结论 改进后的工艺适合工业化生产。     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

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Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.